Oh, and there is one more area where Perry has been a vocal leader: the Tenth Amendment of the U.S. Constitution, which asserts that those powers not enumerated in the Constitution are reserved for the states or the people.

FORBES: Is Gov. Rick Perry Running for President?

From a foreign policy perspective, she adds, it is also a smart move for the United States to strengthen its economic ties with several key countries in a region with at least one vocal anti-American leader, Hugo Chavez of Venezuela.

FORBES: Free Trade Deals: Where Are We Now?

It supported President Mohammed Morsi during the June presidential elections but later became increasingly vocal in its opposition to the Islamist leader.

BBC: Egypt detains leading youth activist Ahmed Maher

In addition, Merkel allied Germany with the U.S. to oppose Iran's nuclear activities, and she was vocal on energy security at the G8 summit meeting this summer, where she was the only female leader at the table.

FORBES: Magazine Article

At the same time, Merkel also has allied Germany with the U.S. to oppose Iran's nuclear activities, and she was vocal on energy security at the G8 summit meeting this summer, where she was the only female leader at the table.

FORBES: The World's Most Powerful Women